1. Field of the Invention
The present invention relates generally to the field of communication devices and, more specifically, to speakerphones and video conferencing systems.
2. Description of the Related Art
A videoconferencing system may include a microphone and a plurality of speakers. The videoconferencing system may receive a remote audio signal from a remote system and transmits the remote audio signal from the plurality of speakers. Thus, the remote audio signal radiates into space so that local persons can hear the voices of other persons situated around the remote system. Unfortunately, this transmission of the remote audio signal (from the speakers) and the reflections of this transmission are picked up by the microphone. Thus, the signal received from the microphone includes a combination of (a) the voice signals generated by local participants and (b) the multi-path interference due to the remote audio signal transmission. Thus, a videoconferencing system may perform echo cancellation in order to remove (b) from the microphone input signal, leaving a cleaner representation of (a). However, the echo cancellation task is made more difficult because the remote audio signal may be transmitted from different speakers at different times, or, different combinations of the speakers at different times. Thus, there exists a need for more robust echo cancellation systems and methodologies capable of handling such situations.